WBIX's old Gates

And here is that old MW-50, still in service, but now just a
backup for the BE. Its serial number is 90954, and it was
originally built for operation at 680 kHz. (Is this an old WRKO
transmitter, perhaps?) Somewhat unusually, it was also built
for an RF line impedance of 75 ohms—50 would be more usual
today.